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About this blog

I'm a well-known mainframe performance guy, with almost 30 years of experience helping customers manage systems. I also dabble in lots of other technology. I've sought to widen the Performance role, incorporating aspects of infrastructural architecture.
I'm a world-famous podcaster and screencaster (albeit VERY thinly spread). :-)

Usually when I go away on holiday I bring something back with me. Often in the form of fresh ideas. This year it's been such a hectic one that all I did was to flake out. So no new ideas this time. Perhaps that's a good thing, perhaps not. But I think I did achieve something: Mental decluttering. So I can, for example, look at stuff I was working on with a fresh take. And the timing is... [More]

To whoever it is in Denmark that's repeatedly hitting my blog today with a search for "dyndisp" and "ddf" I'd love to know what it is that is causing you to search for those two terms together. As you're on my (day job) patch perhaps I should be talking to you directly. So feel free to contact me by clicking on this link . (I'm hoping the "mailto:" URL form works on your system.) And, yes, I am... [More]

With just over a week to go I've got my presentation materials in for this great conference: IBM System z Technical University 21-25 May in Berlin. I hope to see many friends - old and now (old and young) there. For the record my three sessions are: zZS08 - I Know What You Did Last Summer zZS18 - Optimizing z/OS Batch (repeats) zZS21 - Parallel Sysplex Performance Topics And, as well as seeing... [More]

We must have over 200 iOS apps in our iTunes account.
Some of them we paid for, but usually not much 1 , but many were free. 2 I'm sure I'm not alone in wondering "how did that happen?" It's got well beyond the point that a new app 3 simply won't appear on my iPhone and has to be searched for.
Yes, I do use app groups and yes I also know how to find the recently used apps but that's... [More]

You could consider this another in the Small Programming Enhancement (SPE) series.
You’ll probably also notice I’ve been doing quite a lot of REXX programming recently.
Anyway, here’s a tip for refactoring code I like. Suppose you have a line of code: norm_squared=(i-j)*(i-j)
that you want to turn into a function. No biggie: norm2: procedure
parse arg x,y
return... [More]

In October Frank Kyne and I expect to run a residency in Poughkeepsie.
You can find the announcement here . The residency builds on the ideas presented here and three subsequent posts. I revisited a specific part of it in
Cloning Fan-In . So what are we going to do? For a start we're going to assemble a team of 4 skilled mainframe folks from wherever we can. One of them will be me, which leaves... [More]

Or should that be "Subjective Data And The Bad Mood"? A good friend of mine says that when dispensing advice one shouldn't use "may" or "might",
but that one should be more definite. I've probably said this before: When I say or write "may" or "might" I'm deploying the
subjunctive mood for what I hope aren't "weasel words" reasons.
My claim would be the subjunctive mood reflects some underlying... [More]

This is really just a test of some Firefox Extension code of mine... but it's kind of interesting in its own right... The following is a table containing the country-level summary of Search URLs that somehow get a reader to my blog on any given day. (I have another table ranking search terms.) Most days the USA and India are at the top of the list. And there's usually a smattering of other... [More]

First, a belated Happy New Year! to everyone. It's been a busy past few weeks, not least because of the customer situation I'm working on. But, to kick off 2013 here are the two conference abstracts I submitted for the UKCMG Annual Conference. No pressure, guys. Time For DIME In recent years memory has become cheaper, or certainly more plentiful. This enables us to do new things, or old... [More]

As many people know I've been a Queen fan since 1974. And us Queen fans all know how we feel about Freddie Mercury's death and the subsequent retirement of John Deacon. So it was with a mixture of anticipation and trepidation that I saw Queen + Paul Rodgers live in Hyde Park this summer. That was a great show. As these guys are all about 15 years older than me it's nice to see that in a... [More]

A friend of mine from the ITSO in Poughkeepsie is contemplating a Red Paper on Coupling Facility Capacity Planning. I think this is a splendid idea - and would be willing to contribute myself. But I'm wondering what y'all think of the idea. And of what you'd like to see in such a Red Paper. (Red Papers are less formal than Red Books - which we all know and love.)

Yesterday we IBM "pioneer" bloggers had a conference call where we thought about enhancements to this blogging site. One that seemed to get some measure of support was the notion of a place where readers could make unsolicited comments and ask questions. I'm just writing about things I think are interesting. I'm not sure what my readership want to hear about. So I'm going to take a risk and invite... [More]

I presented a set of (someone else's) foils on Web 2.0 to my team meeting last week. (Interestingly, being 6 months old they were already way out of date - what with Twitter and all.) Remember I'm in a mainframe crowd of effectively "gurus". :-) So why should they be interested in new-fangled webby stuff? So I got to thinking... Dear reader, why should you care about Web 2.0? The minimal answer is... [More]

I've just created a wiki to discuss primarily SMF. Mainly from the management perspective, rather than the contents of each individual record. This follows on from things I've mentioned in this blog before. If you'd like to contribute to it (and it is DESPERATELY in need of contributions right now) get a developerWorks screenname and send it to me here . Then I'll enable you to edit the wiki. You... [More]

As I’ve indicated elsewhere we use iThoughts for outlining our podcast episodes (and use it to track completion). I’ve developed quite a nice technique for iThoughtsX (the macOS flavour), which I’ll share with you. This is in case you’re inclined to play with newer toys. Consider the following fragment of an outline: You’ll see some of the nodes are filled (arguably)... [More]

A couple of items from the world of music caught my attention recently - and there's some commonality between them: According to Dave Grohl of Foo Fighters' blog post: Hey everybody, Dave here' "From day one, the idea for this record was to make something completely simple and honest, to capture that thing that happens when you put the 5 of us in a small room. No big production, just real rock and... [More]

I've just been looking at some fascinating SMF 70 records. They come from a System z9 EC S54 machine and the LPAR they're from is running z/OS Release 8. I say "fascinating" because: I've not seen an S54's data before. (This is the largest z9 machine - with all 4 processor books fully populated with engines.) There are changes that I asked RMF (and PR/SM) Development to add into Release 8 that I'm... [More]

I'm going to try something different this year – and composing this using OpenOffice Writer on my new ASUS EEE PC while flying home is certainly different. But what's new is not documenting all the bits and pieces I learnt. Instead I'm going to give some impressions: On Monday afternoon we had an enforced evacuation from the conference centre and much of the environs – because of a World War II... [More]

Long ago the DB2 REORG utility traded memory for speed with SORTKEYS and SORTDATA. The latter caused the object being REORGed to be unloaded and externally sorted (eg using DFSORT). (SORTKEYS was similar but for the keys to REORG the indexes.) This is fine if you have the memory to drive either large in-memory sorts or multiple parallel sorts. But sometimes you don't. APAR PK18059 for V8... [More]

Just a brief follow on to Bad Data And The Subjunctive Mood : Here's a podcast I like to listen to while running.
(Music and podcasts are about the only thing that keep me running, that and the success at my modest goals.)
BBC Radio 4 has a very nice programme More Or Less: Behind The Stats .
It's a magazine programme with extremely digestible yet thought-provoking items on Statistics. My... [More]

I feel like I'm on "home turf" at UKCMG... My use of English can be looser :-) and it's so nice to catch up customers with whom I've a long and (I hope) fruitful history. I did my (slightly updated) "Memory Matters" and "Much Ado About CPU" presentations - and I really do lose track of how much change there's been in each of them (though it seems to me I fiddle with them A LOT. :-) Actually I sat... [More]

A couple of days ago I had a need to take a REXX string comprising space-separated numbers and find their minimum and maximum values. Here's the technique I used. (When I say "space-separated" there can be one or more spaces between the numbers, but there has to be at least one.) The solution has three components: The REXX SPACE function - to turn the list into a comma-separated string of... [More]

I've not really gotten into EWLM and ARM - yet. But I think this APAR will be of interest to those who have. And I expect I will get interested in it when it's more fully established... PK11801 DDF FULLY-ENABLED EWLM ARM SUPPORT describes how the DDF support for EWLM / ARM is being made available to the general population of DB2 Version 8 sites. To quote: DB2 for z/OS' support for EWLM was... [More]

I previously mentioned the change in zNALC LPAR setup... You can (with APAR OA20314) now specify LICENCE=ZNALC. The SCRT co-requisite is Version 14.1.0. By the way, from when you submit your SCRT report at the beginning of August you have to use this new version (until a new one is mandated) in order to be eligible for Sub-Capacity Pricing. There are a number of other changes, some of which are... [More]

This post is meant to inspire people who like programming the web to do simple tasks.
It contains a sample Firefox GreaseMonkey [1] script, which I hope you will find useful. [2] Suppose you are looking at a web page, perhaps one with a table in, and you want to add up some numbers you see there.
Perhaps they’re in a column in that table. With this script you select the numbers... [More]

In zIIP Address Space Instrumentation I discussed the subject of zIIP Capacity Planning. What I was working on - but wasn’t ready to reveal - was a presentation on zIIP Capacity Planning.
But I was also working on my new “zIIP CPU From Type 30” code.
And that’s indeed what that post is about. Now I am in a position to reveal my new presentation.
You can get it from here... [More]

“Mobile” appears to be “flavour of the month” right now, and this week at System z Technical University it has certainly been a topic in evidence, whether it’s discussions in the breaks, sessions on software pricing, or sessions on Mobile-enabling technology. I don’t intend in this post to discuss any of these. Instead I want to talk about the types of users... [More]

I present at conferences on what I call New World DB2 application performance, by which I mean such things as Stored Procedures, SAP R/3 and BW, Distributed (DDF) and JDBC. I do this because I think us mainframe performance people need to lead conversations on DB2 application performance that actually acknowledge what the installation is trying to do with DB2. Often it's not the common or garden... [More]